The Z-tube is an experimental apparatus for measuring the tensile strength of a liquid.
It consists of a Z-shaped tube with open ends, filled with a liquid, and set on top of a spinning table. If the tube were straight, the liquid would immediately fly out one end or the other of the tube as it began to spin. By bending the ends of the tube back towards the center of rotation, a shift of the liquid away from center will result in the water level in one end of the tube rising and thus increasing the pressure in that end of the tube, and consequently returning the liquid to the center of the tube. By measuring the rotational speed and the distance from the center of rotation to the liquid level in the bent ends of the tube, the pressure reduction inside the tube can be calculated.
Negative pressures, (i.e. less than zero absolute pressure, or in other words, tension) have been reported using water processed to remove dissolved gases.[1] Tensile strengths up to 280 atmospheres have been reported for water in glass.[2]
References
[edit]- ^ Smith, Andrew M. "Negative Pressure Generated by Octopus Suckers: A Study of the Tensile Strengths of Water in Nature," J. exp. Biol., 157, 257-271, 1991.
- ^ Denny, Mark (1993). Air and water: the biology and physics of life's media. Princeton University Press. ISBN 0691025185.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction